Cronofy, the U.K. startup that offers a calendar API to help businesses and their customers synchronise calendars, has raised a $1.6 million seed round led by Firestartr alongside Amsterdam-based venture capital firm henQ.

The investment comes post-pivot after the company dropped its rather convoluted consumer offering, called One Diary, to focus purely on its then fledgling B2B model.

In similar fashion, Cronofy handles the heavy lifting required to deal with the “plumbing and technical synchronisation issues” inherent when integrating with multiple calendar services and, most crucially, keeping those calendars in sync.

Customers cited by the startup include flight search engine Skyscanner, which is using the Cronofy API as part of its new TravelPro service which sees a customer’s itinerary pushed automatically to their calendar and kept up to date with any flight changes.

Another example is Applicant Tracking Systems (ATS) providers who are using Cronofy to streamline the interview booking process, co-ordinating the relevant staff members’ calendars and the applicant’s.

“Importantly this can be kept up to date as people’s availability changes and the moment the candidate chooses a slot, it’s in everyone’s calendars,” explains Bird.

In addition, the so-called ‘gig economy’ is also finding a use in Cronofy’s service. For example, Zesty is using the API to get access to real-time availability for their physiotherapists, osteopaths etc. so when a user books online they can be confident that the professional is available.

“The moment a booking is made they use us to push it straight to the professional’s calendar. Real time sync is critical to a great user experience,” he says.

To that end, Richard Muirhead, co-founder and chairman of Firestartr, says in a statement: “Synchronising schedules has become critical for many millions more people, driven by smart phones, the gig economy and crazy calendars. Software developers crave easy ways to embed great functionality into their apps and websites, so we really like Cronofy’s developer-driven route to market.”